1. Field of the Invention
The present invention relates to an apparatus for insulating a battery, and more particularly to an apparatus which provides for air flow about the battery when the battery is being used but which confines the air to the area surrounding the battery when the battery is not in use.
2. Description of the Prior Art
In U.S. Pat. No. 3,837,918, issued to Nakabayashi on Sept. 24, 1974, there is disclosed a sodium sulfur storage battery which includes an air space surrounding the battery elements and pipes leading into and out of the air space. A temperature detector is utilized to control electromagnetic valves to maintain the battery at the constant temperature. The Nakabayashi patent is directed at a very special type of battery system which incorporates molten sulfur and sodium as the cathode and anode, respectively. The concern in the Nakabayashi device is to prevent the molten reactants, which are maintained at about 350.degree. C., from damaging the containing vessel. A coolant is therefore piped through the space defined by the apparatus.
In U.S. Pat. No. 3,767,468, issued to Schusler on Oct. 23, 1973, there is described a battery apparatus which includes air cooling means. The battery container defines passages through which air is conducted to cool the battery. Related battery constructions are disclosed in U.S. Pat. Nos. 3,238,070, issued to Porter on Mar. 1, 1966; 2,666,091, issued to Martin et al. on Jan. 12, 1954; and, 2,410,952, issued to Lighton on Nov. 12, 1946. Each of these patents describes a battery construction which includes an insulating passageway surrounding the battery elements. In none of these patents, however, is there disclosed a battery insulating apparatus which includes vents operable to permit natural air flow about the battery while the battery is in use and which further retains the warm air around the battery when the battery is not in use. Further, none of the patents disclose vent means operable by an engine to which the battery is connected to permit air flow about the battery only when the engine is operating.